Sökning: "finite element method FEM"

Visar resultat 1 - 5 av 158 avhandlingar innehållade orden finite element method FEM.

1. 1. Finite Element Procedures for Fluid-structure Interaction

   Författare :Joakim Hermansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nitsche s method; stabilized Crouzeix-Raviart; Winslow s method; Raviart-Thomas; space-time FE; stretched elements; FSI; FEM; weak coupling; mesh smoothing; acoustic FSI; ALE;

   Sammanfattning : This thesis concerns finite element (FE) methods for solving fluid-structure interaction (FSI) problems. Two types of fluid-structure interaction are considered. A finite element method for solving the interaction between a flowing incompressible fluid and a linear elastic structure is proposed. The flow is assumed to be laminar. LÄS MER

3. 2. Structural-acoustic vibrations in wooden assemblies : Experimental modal analysis and finite element modelling

   Författare :Åsa Bolmsvik; Torbjörn Ekevik; Andreas Linderholt; Anders Brandt; Anders Ågren; Linnéuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wooden framed structure; light weight buildings; multi-storey; flanking transmission; junction; vibration distribution; impact noise; damping; elastomers; finite element analysis; experimental modal analysis; FRF; trästomme; träkonstruktion; träbyggnad; flervåningshus; EMA; FEM; flanktransmission; koppling; knutpunkt; vibrationsspridning; stomljud; stegljud; dämpning; elastomerer; finit elementmetod; experimentell modalanalys; accelerationsmätning; frekvensresponsfunktion; modalanalys;

   Sammanfattning : This doctoral thesis concerns flanking transmission in light weight, wooden multi-storey buildings within the low frequency, primarily 20-120 Hz. The overall aim is to investigate how the finite element method can contribute in the design phase to evaluate different junctions regarding flanking transmission. LÄS MER

4. 3. A hybrid finite element method for electromagnetics with applications in time-domain

   Författare :DAVID DEGERFELDT; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nitsche s method; antenna arrays; NASA almond; edge elements; scattering; explicit-implicit time-stepping; Maxwell s equations; Finite Element Method; mass lumping; stability analysis; Finite-Differences Time-Domain; periodic structures; shape and material optimization;

   Sammanfattning : In this thesis, a new hybrid method that combines the Finite Element Method (FEM) with the Finite-Difference in Time-Domain (FDTD) method is presented. Tetrahedrons in the unstructured FEM region are connected directly to thehexahedrons in the structured FDTD region. LÄS MER

5. 4. On the Arbitrary Lagrangian-Eulerian Finite Element Method

   Författare :Lars Olovsson; Kenneth Runesson; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; large deformation plasticity; FEM; ALE; multi-material Euler; machining simulations;

   Sammanfattning : This thesis has been devoted to the study and development of algorithms for Finite Element (FE) simulations of mechanical processes involving large deformations. Aspects of three different formulations have been considered:(i) The single material Arbitrary Lagrangian-Eulerian (ALE) formulation is a method where the FE mesh is allowed to move independently to the material flow. LÄS MER

7. 5. High-Performance Finite Element Methods : with Application to Simulation of Diffusion MRI and Vertical Axis Wind Turbines

   Författare :Van-Dang Nguyen; Johan Hoffman; Johan Jansson; Axel Målqvist; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; High performance finite element method; computational diffusion MRI; turbulent flow; vertical axis wind turbine.; Computer Science; Datalogi;

   Sammanfattning : The finite element methods (FEM) have been developed over decades, and together with the growth of computer engineering, they become more and more important in solving large-scale problems in science and industry. The objective of this thesis is to develop high-performance finite element methods (HP-FEM), with two main applications in mind: computational diffusion magnetic resonance imaging (MRI), and simulation of the turbulent flow past a vertical axis wind turbine (VAWT). LÄS MER